Thank you for writing.
It is a known problem with FormWindowState.Maximized
. You can track its progress, subscribe for status changes and add your vote/comment to it on the following link - feedback item
Unfortunately, I can not suggest a suitable solution. Instead of maximizing the form, you can increase its size to simulate the maximized state without overlapping the taskbar at the bottom.
I hope this information helps. Should you have further questions I would be glad to help.
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